Our research over the last 8 years suggests that most sickle cell pain is managed at home by older children and adolescents, and by families of infants and young children. In this grant proposal, we will continue to determine the incidence of vaso-occlusive and other pain in infants and young children with SCD using parental daily reports, and where appropriate, child self-report as these children reach school-age. Daily parent-report formats will utilize a combination of daily email or automated phone report and staff initiated bi-weekly telephone interviews for parents of infants, followed by electronic daily diaries using PDAs for parents of young children; all of which will have considerable advantages compared with the previous use of paper diaries. We will also examine, in conjunction with Project II, the relationship between the incidence and/or frequency of sickle pain in these infants and various hematologic and biologic parameters. The focus of this investigation will expand beyond the relationship between pain incidence, fetal hemoglobin, erythrocyte endothelial cell adhesion, and coagulation activation, to include measures of WBC, platelet, and endothelial cell activation. Based on information from parent report and our clinical experience, for our second project Aim, we will develop, implement, evaluate, and disseminate a parentmediated home pain management protocol for the management of sickle pain in infants and young children. These management protocols and their associated educational materials will address some of the pain management issues identified in our previous studies, including inadequate dosing and frequency of analgesics, and inadequate assessment and reassessment of pain. The availability of reliable communication between family and the healthcare team and programmable PDAs will provide a unique opportunity to implement and evaluate such a program. Finally, we will examine several theoretic and empirical models from the pediatric pain and pediatric psychology literatures for their usefulness in explaining relationships between psychosocial factors (e.g., coping strategies, parent-child interactions) and the self-report of pain, (functional impairment) and quality of life (disability) in school-age children and adolescents with SCD. These studies will examine these factors in a cross-section of children with SCD in mid-childhood (7-12 years old) and adolescence (13-17). These ages are selected because self-esteem and a sense of competence develops in children during mid-childhood, and we clinically begin to see the development of recurrent pain syndromes in mid-childhood as well. Examining the dynamics influencing effective and ineffective pain self management skills will provide information for increasing competence in these children that will provide preliminary information that could be used to develop future interventions for our longitudinal cohort when it reaches mid-childhood.